Class1, Division 2 or not??

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James539

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I have a storage room that will contain less than 1375 gallons of ethanol at either 100% or 70% concentration and stored in specimen jars (approx 1 pt each). According to NFPA 30 and stated by a professional fire protection engineer, ethanol in these concentrations is classified as a Class 1 group B material and quantities less than 1375 gallons mean "the existing room is generally compliant". The fire protection engineer further states "If acceptable protection is not available in NFPA 30 Section 4.8 or via full-scale testing, the storage is considered 'unprotected' and cannot exceed 1375 gallons".

My question to all of this is:

Does the Class1, Divison 2 hazard classification per NEC 500.5 (B)(2) apply in this situation and should I replace the existing electrical to be Class 1, Div2 compatible?
 

rbalex

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Re: Class1, Division 2 or not??

I'm making the (possibly wild) assumption that this is a continuation of this topic.

There are some anomalies here. First, ethanol is a Group D (not B) flammable liquid. Second, there is no Section 4.8 in the current NFPA 30 and Chapter 4 deals with bulk storage or portable tank storage greater than 3000L (793 gal.) rather than small containers.

So, let's clear these items up first and go from there.
 

James539

Member
Re: Class1, Division 2 or not??

You are correct on your assumption. Also note the glass container in question is limited to under 1 gallon.

The AHJ identifies the material as Class 1-B flammable alcohol and client says its Class 1-B ethanol at 70%. (no MSDS's to identify material). The material class and grouping is being investigated.

The state that this room is in has adopted NFPA 30 per AHJ. The AHJ in their letter identifies CH. 4 (4-4.4.1)of NFPA 30, "container storage of Class 1B liquids in unprotected cutoff rooms shall not exceed 1375 gallons". Therefore, the fire prot. eng. might have a typographical error in his letter. (Further questioning to this engineer is in order)

Assuming the NFPA 30 code chapter is correct on it's quantity, what would be the answer to the above question about class1, div2?
Originally posted by rbalex:
I'm making the (possibly wild) assumption that this is a continuation of this topic.

There are some anomalies here. First, ethanol is a Group D (not B) flammable liquid. Second, there is no Section 4.8 in the current NFPA 30 and Chapter 4 deals with bulk storage or portable tank storage greater than 3000L (793 gal.) rather than small containers.

So, let's clear these items up first and go from there.
 

rbalex

Moderator
Staff member
Location
Mission Viejo, CA
Occupation
Professional Electrical Engineer
Re: Class1, Division 2 or not??

The citation 4-4.4.1, rather than 4.4.4.1 (a ?dash? rather than a ?point?) indicates to me that the AHJ is referring to an out of date version of NFPA 30. Not that it matters much since there isn?t a Section 4.4.4.1 in the current version of the Code either. The current reference is 6.4.4.1.

I also recognize the reference to ?Class IB? now. That simply means it is a flammable liquid with a flash point below 73F and a boiling point at or above 100F. It is nevertheless a ?Group D? material, which is based on different criteria.

All that being said, there are simply too many criteria in Section 6.4 to make any absolute statement. Criteria such as maximum container size (generally a quart maximum), spacing between palletized containers, overall size of the room, ventilation and other fire prevention means all play into it.

Conversely, Table 8.2.2 makes the absolute statement that inside rooms or storage lockers used for the storage of Class I liquids (which ethanol is) shall be Division 2 for the entire room without reference to any other criteria, although there is some ambiguous content in Sections 8.2.2 and 8.2.3 that theoretically governs the interpretation of the Table.

For what it?s worth, Table 515.3 in the NEC says the same thing; however its scope is limited to bulk storage.

At this point, I?d simply go along with your Fire Protection Engineer?s recommendation. If he does go with Division 2 through out ? I?d follow my recommendations from the other thread for the installation :D
 

James539

Member
Re: Class1, Division 2 or not??

Thank You for Your interpretation. However, Table 515.3 poses more questions.

1. Does the Class 1, Div2 classification extend beyond the room in this situation, especially at openings and how far (radius)? Does the HVAC play a part in this distance? Note: Table 515.3 does note identify this type of 5th floor room. If so, would the distances in section 516.3(B)(4) [3ft radius] be appropriate eventhough it only pertains to spray booth applications?

2. A known non-explosionproof fume hood is to remain in this area and to be converted to class1, div2 or replaced. Will the fume hoods known non-classified (class1,div2) exhaust fan, located on the outside wall of the building requrire a changeout to class 1 fan (class IB liquid has flash point below 73 degrees F, per NFPA 30)? I am assuming it will, but Section 515.125 identifies in a class 1, div 1 or div2 location only and the extension of class beyond a room opening per question 1 is not yet known.
Originally posted by rbalex:
The citation 4-4.4.1, rather than 4.4.4.1 (a ?dash? rather than a ?point?) indicates to me that the AHJ is referring to an out of date version of NFPA 30. Not that it matters much since there isn?t a Section 4.4.4.1 in the current version of the Code either. The current reference is 6.4.4.1.

I also recognize the reference to ?Class IB? now. That simply means it is a flammable liquid with a flash point below 73F and a boiling point at or above 100F. It is nevertheless a ?Group D? material, which is based on different criteria.

All that being said, there are simply too many criteria in Section 6.4 to make any absolute statement. Criteria such as maximum container size (generally a quart maximum), spacing between palletized containers, overall size of the room, ventilation and other fire prevention means all play into it.

Conversely, Table 8.2.2 makes the absolute statement that inside rooms or storage lockers used for the storage of Class I liquids (which ethanol is) shall be Division 2 for the entire room without reference to any other criteria, although there is some ambiguous content in Sections 8.2.2 and 8.2.3 that theoretically governs the interpretation of the Table.

For what it?s worth, Table 515.3 in the NEC says the same thing; however its scope is limited to bulk storage.

At this point, I?d simply go along with your Fire Protection Engineer?s recommendation. If he does go with Division 2 through out ? I?d follow my recommendations from the other thread for the installation :D
 

rbalex

Moderator
Staff member
Location
Mission Viejo, CA
Occupation
Professional Electrical Engineer
Re: Class1, Division 2 or not??

As I said earlier:
... there are simply too many criteria in Section 6.4 [of NFPA 30-2003] to make any absolute statement. Criteria such as maximum container size (generally a quart maximum), spacing between palletized containers, overall size of the room, ventilation and other fire prevention means all play into it.
...
I'm very reluctant to make "hard" electrical area classification recommendations about facilities/processes that I'm not familiar with. Once the electrical area classification has been determined and documented as required by 500.4(A), I'm much more comfortable about discussing installation requirements.

As I understand your situation so far, Table 515.3 does not apply to you. I was simply mentioning that it uses the same verbiage used in NFPA 30-2003, Table 8.2.2.

Someone familiar with your application AND the principles of electrical area classification needs to make the determination and documentation. BTW this is a FedOSHA "Process Safety Management" requirement too. The process of determining electrical area classification is usually fairly straight-forward, but is isn't a trivial exercise and needs to be done by someone properly trained to do it.
 
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